Speaking in Parliament on Tuesday, the official said there will be months of talks as the EU finalises its spending plans for the post-2020 period.
Crețu said that the European Commission will soon launch a public consultation exercise on the future of cohesion policy and regional funding for the next 10 years.
This, she told a meeting, is likely to involve a radical rethink of how EU regional funds are distributed across Europe.
The Commission is expected to announce a draft EU budget for the next decade in May.
Crețu said, “Money is not everything and it will be important to have trust, not least in how and where regional funds - taxpayers’ money - are allocated in the future.
“Trust must be at the heart of cohesion policy for the post-2020 period and this involves building a good administrative capacity at the national and local level. This is very important.”
She was addressing a debate about the future of structural funds and the role of local administrations in central and eastern Europe, organised by the Bucharest-Ilfov Regional Development Agency (ADRBI).
The Commissioner agreed with other speakers that regions in this part of Europe still had to catch up with similar sized areas in western parts of Europe.
This was across a range of areas, including water management, waste treatment and basic infrastructure, she noted.
But she pointed out that in the 2014 to 2020 spending period, about €15bn from regional funding had been allocated to cities.
She added, “The success of cohesion policy in the future will rest on its ability to bring on board thousands of partners, all linked by a sense of trust and who all seek a better future for their communities.”
Another keynote speaker was Cosmin Boiangiu, Romania’s deputy permanent representative to the EU, who called for rules on cohesion policy to be simplified in order to cut red tape and make things easier for regions and local authorities.
He also called for more effort to promote regional funding, describing it as an important pillar for EU development, and said that considerable effort was needed to build more trust in the policy.
Regional funds had raised living standards for many Europeans and had a significant impact on national economies but he agreed that, with pressure on national and EU purse strings, efforts to preserve regional funding at current levels will not be simple.
He said that some 45 per cent of investment in his country last year had come from regional funding but that disparities still existed between Romanian regions and those elsewhere in the EU.
“That is why investment from cohesion policy must continue,” he insisted.
The meeting was attended by representatives from local authorities in Romania and opening the debate, Ana-Claudia Tapardel, a Romanian MEP, said her country relied on regional funds not just as a source of finance but also for technical expertise from the EU side.
She called the policy “one of the most important instruments” at the EU disposal for levelling disparities between cities and regions across Europe, many of them in east European member states like Romania.
Tapardel, who helped organised the meeting, said, “We should not ignore these disparities and we need this dynamic instrument - cohesion policy - to help continue to level out these regional differences.”
She pointed out she had worked for the local authority in Bucharest for many years and was therefore fully aware of how important regional funds were, as well as the negative impact the 2008 financial crisis had at local level.
“Regional funding is a fundamental policy of the EU and will be more important than ever in the future in order to further reduce these disparities that still exist, especially in eastern European regions.”
Some have questioned the viability of such funding but, despite facing other challenges such as migration and terrorism, she told the meeting it had to remain.
Another MEP, Iskra Mihaylova, who chairs Parliament’s regional development committee, told the meeting that more support was needed for regions to implement regional funding.
The Bulgarian ALDE group member said, “Looking forward, we need to create a new vision for EU cohesion policy and one that that is needed is to make it more flexible so that the policy is closer to the needs of our citizens.”